Blasting device



June 15, 1937.

A. HARRXS BLASTING DEVICE Original Filed June 14, 1955 x y WEN.

NMN

Patented June 15, 1937 BLASTIN G DEVICE Allyn Harris, Chicago, IlL, assignor to Safety Mining Company, a corporation 01 Illinois Application June 14, 1933, Serial No. 675,698 Renewed October 8, 1934 28 Claims. (Cl. 102-6) Th s invention relates to a type of blasting introduction of high pressure air into the chamoartrldge as illustrated in the pending applicaher is to force the valve firmly against its seat t1on of Frank H. Armstrong, Serial No. 673,385 on the discharge cap by reason of the action of filed May 29, 1933. such pressure upon the area presented by the 5 The ob ect of the invention is to provide an plunger. It will be observed in this connection improved means for effecting the discharge of a that the area of the plunger which is exposed to cartridge of this type. Another object is to propressure from the chamber 4 is less than that v de improved means for automatically effecting exposed to pressure from chamber 5 by an amount c a e of the blasting charge from the carequal to the cross sectional area of the rod on tr1dge when a predetermined blasting pressure which the p un a valve are mounted- 10 is attained within the cartridge. Yet another ob- Hence, there is normally difierential tending to wet 1s to provide an improved rupturable presmaintain the valve in closed DOSitiQH- sure release m ns adapted to rupture upon the In order to effect the discharge of a cartridge attainment of a predetermined pressure within of this type t s merely necessary to efiect the cartridge for effecting automatically release rapid decrease in pressure within the chamber 16 0f the blasting charge. These and other ob- 5, thus resulting in a reverse differential presjects will, however, hereinafter more fully apsure condition wherein the pressure exerted on D the plunger from chamber 4 exceeds that exerted Referring to the drawing, thereon from chamber 5, with a consequent axial Figure 1 is a view in longitudinal section movement of the entire difierential valve mecha- 20 through a cartridge of the type indicated and nism. According to the present invention, this m y ng the principles of the present invendrop in pressure within chamber 5 is efiected tron. automatically upon the attainment of a pre- Figure 2 is a sectional detailed view illustratdetermined pressure in that chamber. To this mg a slight modification of the device shown in end, there is provided in the terminal cap 2 a 25 F gure relatively large bore I2 which is normally closed The cartridge consists" essentially of a tubular or sealed by a disc II held firmly in place by a body I, a terminal cap 2 and a discharge cap 3. nut Ill. It has been found in practice, however, The interior of the cartridge provides a chamber that by appropriate selection as to material and 4 designed to receive a substantial volume of po thickness, the disc II can be relied upon to fail 30 tential energy, preferably in the form of high at any desired predetermined pressure. A very pressure air or other gas. Disposed axially withthin disc made of mild steel has been found most in the cartridge is a differential valve mechasuitable for this purpose, although fibre or other nism consisting of a valve head designed to have materials may be effectively used.

85 sealing engagement with the end of discharge Assuming that the particular work to be percap 3 for closing the discharge orifice therein. formed will require a charge of air or other gas -On the opposite end of the rod which carries the at approximately 6500 pounds pressure, a disc I l valve head there is provided a plunger slidably designed to fail or shear out at this pressure is fitting the bore 5 formed in the terminal cap 2. selected and securely positioned in the terminal This plunger is provided with a plurality of ports cap 2. When this has been done, high pressure 40 extending entirely therethrough, which ports are air may be allowed to pass from the receiver or normally closed by a spring compressed disc compressor 6 through the pipe 1 into chamber 5 check valve as shown. of the cartridge, which results, as described The charging passage 9 indicates with the above, in the immediate closing of the differential chamber 5 and with piping or tubing 1 extending valve. The continued flow of high pressure air 5 to a source of high pressure air 6 which may take into the chamber 5 will in a very short space of the form of a compressor or of a high pressure time result in the attainment of a pressure value air or gas receiver. A suitable fitting 8 is proof the desired 6500 pounds, at which point the disc II will shear out, thus providing a rapid escape for the high pressure air contained in the cham- .10 her 5 and resulting in a correspondingly rapid drop in pressure in this chamber. It will be understood, of course, thatimmediately upon failme of the disc II the operator at the compressor or air receiver should close the valve, thus dis- 55 vided for coupling pipe I to the terminal can 2. Thus, high pressure air or other gas may be introduced into the chamber 5 resulting in the opening of the disc check valve and in the passage of the air through the several ports formed in the plunger and thence into the main charge receiving chamber 4. The initial effect or the .exerted upon the opposite face of the plunger from chamber 5 that the differential valve mechanism immediately moves to open position and by reason of the rapidity of the escape of high pressure air from the chamber 5 and of the drop in pressure therein, the differential valve mechanism will remain in open position until the entire charge has been exhausted from chamber 4 through the discharge cap.

A slight modification is represented in Figure 2 which consists essentially in restricting the rate of flow of air from'chamber 5 after the disc H hasbeen sheared. This is accomplished by providing a small passage l3 communicating with the. larger bore l2 which the disc II is designed to seal. By thus restricting the rate of flow of air from the chamber 5 the difierential valve mechanism is caused to alternately open and close in rapid succession several times in effecting the discharge of the high pressure air contained in the main chamber 4. This alternate opening and closing action results from the fact that the initial opening of the difierential valve causes an instantaneous pressure drop in the main chamber 4 to a value below that which has been attained in the chamber 5 due to the restricted flow from the latter chamber. Hence, the pressure in chamber 5 again prep onderates and results in the closing of the difierential valve. However, the continued flow from chamber 5 through the restricted passage Hi again results in a drop in pressure below that eidsting in chamber 4, thus resulting in a second opening of the differential valve. This actionis repeated until the entire charge contained in chamber 4 has been exhausted. It may be well to mention in this connection that the disc check valve prevents the flow of high pressure air from the chamber, 4 into chamber 5, thus preventing an equalization of pressure in the two chambers in this manner.

While there is in this application specifically described two forms which the invention may assume in practice, it will be understood that these forms of the same are shown for purposes of illustration and that the invention may be modified and embodied in various other forms -without departing from its spirit or the scope of the appended claims.

1. A material breaking apparatus comprising a cartridge adapted to receive a charge of high pressure air or gas and embodying a discharge .orifice through which such charge may be re- .leased, a differential valve mechanism normally sealing said orifice when pressure exists within the cartridge, and means for eflect ing the opening of said differential valve mechanism automatically' upon the attainment of a predetermined pressure within the cartridge.

2. A material breaking device comprising a cartridge having a discharge orifice, a difierential valve for sealing said orifice, a control chamber for governing operation of said differential valve and a pressure responsive element for venting said chamber to the atmosphere.

-3. A material breaking device comprising a cartridge having a charge receiving chamber and a discharge orifice, a differential valve mechanism for sealing said orifice when pressure in excess of atmospheric exists in the cartridge, said cartridge embodying a control chamber, the pressure wherein governs the action of said differential valve, there being a passage extending from said control chamber to the exterior of said cartridge for venting the chamber to the atmosphere and an element rupturable at a predetermined pressure for normally sealing said passage.

4. A blasting cartridge comprising a casing having a chamber for receiving a charge of high pressure air or gas, release means for said charge constructed and arranged to be normally held in charge retaining position by pressure fluid, and means automatically operative to effect opening of said release means upon the attainment of a predetermined pressure within the cartridge.

5. A blasting cartridge comprising a casing having a chamber for receiving a charge of high pressure air or gas, release means for said charge movable into said chamber to effect charge release, and means automatically operative to effect opening of said release means upon the attainment of a predetermined pressure within the cartridge.

6. A blasting cartridge comprising a casing having a chamber for receiving a charge of high pressure air or gas, release means for said charge movable into and normally held in charge retaining position by pressure fluid in the chamber, and means. automatically operative to effect opening of said release means upon the attainment of a predetermined pressure within the cartridge.

7. A blasting cartridge comprising a casing having a chamber for receiving a charge of high pressure air or gas, release means for said charge constructed and arranged to be held in charge retaining position and to be moved into charge releasing position by iiuid pressure, and fluid pres sure responsive means, for effecting automatic opening of said release means when a predetermined blasting pressure is attained within the cartridge.

8. A blasting cartridge comprising a casing having a chamber for receiving a charge of high pressure air or gas, release means for said charge, and pressure responsive means including a plunger rigidly connected to said release means for effecting automatic opening of said release means when a predetermined blasting pressure is attained within the cartridge.

9. A blasting cartridge comprising a casing having a chamber for receiving a charge of high pressure air or gas, release means for said charge comprising a discharge control valve, fluid pressure responsive means constructed and arranged for eflecting automatic opening of said discharge control valve when a predetermined blasting pressure is attained within the cartridge and for pressing the latter closed during building up of the blasting pressure within the fitridge, and additional fluid pressure responsive means for causing the first mentioned pressure means to automatically open said valve when said blasting pressure is attained.

10. A blasting cartridge comprising a casing having a chamber for receiving a charge of high pressure air or gas, release means for said charge actuated piston rigidly connected to said valve for holding the latter closed during building up of the blasting pressure within the cartridge and for automatically opening said valve when said blasting pressure is attained.

11. A blasting cartridge comprising a casing having a chamber for receiving a charge of high pressure air or gas, release means for said charge, and means automatically operative to effect opening of said release means upon the attainment of a predetermined blasting pressure within the cartridge including a releasable valve means adapted to release automatically upon the attainment of said predetermined blasting pressure to cause said release means to release the charge.

12; In a blasting cartridge comprising a'casing having a chamber for receiving a charge of high pressure air or gas, release valve means for said charge, and means automatically operative to effect opening of said release valve means upon the attainment of a predetermined blasting pressure within the cartridge including a releasable venting means adapted to release automatically upon the attainment of said predetermined blasting pressure.

13. A blasting cartridge comprising a casing having a chamber for receiving a charge of high pressure air or gas, release means for-said charge, and means automatically operative to efiect opening of said release means upon the attainment of a predetermined blasting pressure within the cartridge and including frangible valve means adapted to rupture to effect opening of said release means upon the attainment of said cally operative to effect venting of said control chamber upon attainment of a predetermined blasting pressure within the charge receiving chamber, said passages in said piston being automaticallyclosed when said control member is vented and the pressure in said charge receiving chamber effecting movement of said piston in said control chamber to release said valve means when said control chamber is vented.

15. A blasting cartridge comprising acasing having a chamber for receiving a charge of high pressure air or gas and a control chamber, valve means for releasing the blasting charge from said charge receiving chamber, a piston in said control chamber for controlling said valve means, and means for automatically venting said control chamber to effect movement of said piston to release said valve means when a predetermined blasting pressure is attained within said charge receiving chamber.

16. A blasting cartridge comprising a casing having a chamber for receiving an energy storing charge, and means for automatically eifecting release oi! the charge from said chamber when a predetermined blasting pressure is attained within said chamber and including a pressure controlled discharge control valve movable in a seating direction outwardly of said chamber.

17. A material breaking apparatus comprising a cartridge providing a charge receiving chamber having concurrently movable opposite end walls, means for introducing a charge of gaseous medium into said chamber between said walls, and means for eiiecting movement of said walls automatically upon attainment of a predetermined charge pressure to effect charge release.

18. A material breaking device comprising a cartridge having a discharge orifice, release means for said orifice including a valve opening oppositely of the direction of discharge through said orifice, and means automatically operative to effect opening of said release means upon the,

attainment of a predetermined pressure within the cartridge.

'19. A blasting cartridge comprising a casing having a chamber for receiving an energy storing charge and a fluid control chamber, charged simultaneously with and to the same pressure as said first chamber and means for automatical- 1y efiecting release of the energy storing charge when a predetermined fluid pressure is attained within said control chamber.

20. A blasting cartridge comprising a casing having a chamber for receiving an energy storing charge and a control chamber having communication with said energy storing charge only during charging of the cartridge, and means for automatically effecting release of the energy storing charge when a predetermined pressure is attained within said control chamber.

21. In a blasting cartridge, a casing constructed to confine fluid medium at a blasting pressure, and releasing mechanism for the casing comprising two blasting medium discharging devices both of which are subjected to the same fluid pressure while the casing is charged and adapted to operate to release the medium when one of the devices is subjected to a blasting pressure during charging, and means for causing the operation of said one device to efiect operation of the other device.

22. In a blasting cartridge, a casing constructed to confine fluid medium at a blasting pressure, and releasing mechanism for the casing comprising two fluid pressure responsive blasting medium discharging devices independently mounted in the casing, and means for causing the operation of one of said devices to be dependent upon the prior operation of the other device.

23. In a blasting cartridge, a casing constructed to confine fluid medium at a blasting pressure, and releasing mechanism for the casing comprising two blasting medium discharging devices adapted to operate to release the medium, one of said devices being operated by said medium at a blasting pressure, and means for operating the other of said devices when differential fluid pressures above atmospheric pressure are applied to the same as a result of the operation of said one device.

24. In a. blasting cartridge, a casing constructed to confine fluid medium at a blasting pressure, and releasing mechanism for the casing comprising two cooperatively associated blasting medium discharging devices adapted to operate to release the medium, one of, said devices being a fluid pressure responsive venting device automatically operable when a predetermined pressure is attained within the casing.

25. Inaa blasting cartridge, a casing constructed to confine fluid medium at a blasting pressure and having two blasting medium discharge openings, anda separate fluid pressure respon- 5 chamber for receiving a charge of blasting pressure, a valve for releasing the pressure from said chamber, a piston secured to said valve and controlled by the pressure in said chamber for actuating said valve, and valve means carried by said 10 piston in radially spaced relation to the axis thereof for controlling the supply of, pressure fluid to said pressure chamber.

27. A blasting cartridge comprising a substan tially cylindrical container adapted to receive a 15 high pressure charge and having a discharge opening adjacent one end thereof, valve means closing said opening, releasable means adjacent the other end of said container for holding said valve means in said opening, and means operable automatically in response to the attainment of a predetremined blasting pressure in said container for efiecting release of said releasable means.

28. In a blasting cartridge, a casing constructed to confine fluid medium at a blasting pressure and having two blasting medium discharge openings located at or adjacent the opposite ends thereof, and a separate fluid pressure responsive device for discharging the blasting medium through each of said openings.

ALLYN HARRIS. 

